An electric battery is a device that stores electric energy by means of an electrochemical cell. An electric battery may include a single electrochemical cell or a plurality of electrochemical cells, configured in parallel, series or a combination thereof. An electric battery may use an electrochemical cell to convert chemical energy to electric energy. The basis of this process is to derive electric energy in the form of the liberation of electrons as a result of a chemical reaction. There are multiple rechargeable battery chemistries including Nickel-Cadmium (NiCd), Lead-Acid, Nickel-Metal-Hydride (NiMH), Nickel-Zinc (NiZn), Lithium-Ion and Lithium Polymer. These batteries may be configured as cylindrical cells, button cells, prismatic cells, or pouch cells.
A battery cell comprises an anode and cathode with an electrolyte used to carry ions between the anode and cathode. The result of charging and discharging a battery cell via an electrochemical process may include the release of gas, the generation of heat, or the deposition of material on an electrode. These electrochemical processes may cause the battery cell to swell or expand.
Other components may also be used to store electric energy, for example, a capacitor stores electric energy electrostatically by means of an electric field being applied to two plates separated by a dielectric such that the electrons gather and are held by the electric field.